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NUMERICAL CALCULATIONS OF GASEOUS REACTING FLOWS IN A MODEL OF GAS TURBINE COMBUSTORS

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Chinese Journal of Aeronautics 1991年第1期6卷 26-34页

作者： Yan Chuanjun, tang Ming, zhu Huiling and Sun HuixianNorthwestern Polytechnical University Northwestern Polytechnical Univ

This paper describes the numerical calculations of gaseous reaction flows in a model of gas turbine combustors. The profiles of hydrodynamic and thermodynamic patterns in a three-dimensional combustor model are obtained by solving the governing differential transport equations. The well-established numerical prediction algorithm SIMPLE, the modified k-ε turbulence model and k-ε-g turbulent diffusion flame model have been adopted in computations. The β function has been selected as probability density function. The effect of combustion process on flow patterns has been investigated. The calculated results have been verified by experiments. They are in remarkably good agreement.

关键词： NUMERICAL CALCULATIONS OF GASEOUS REACTING FLOWS IN A MODEL OF GAS TURBINE COMBUSTORS GAS Flow work

Single Particle Colorimetric Acid Phosphatase Activity Assay with CeO_(2)-modified Gold Nanoparticles

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Chemical Research in Chinese Universities 2024年第2期40卷 320-325页

作者： zhu tang Jiayao YUAN Xiang MAO Guojiang WEI Lin XIAO Lehui Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research National and Local Joint Engineering Laboratory for New Petrochemical Materials and Fine Utilization of ResourcesCollege of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha410081P.R.China Henan Key Laboratory of Organic Functional Molecule and Drug Innovation Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang453007P.R.China College of Chemistry and Chemical Engineering Central South UniversityChangsha410083P.R.China

Acid phosphatase(ACP)is a ubiquitous phosphatase in living *** abnormal variation of ACP is related to various ***,we propose a colorimetric method based on CeO_(2)-modified gold core shell nanoparticles(Au@CeO_(2)NPs)to analyze ACP activity with high sensitivity and *** this design,2-phospho-L-ascorbic acid trisodium salt(AAP)is dephosphorylated by ACP and produces reductive ascorbic acid(AA),which makes the CeO_(2)shell decomposition.A remarkable blue shift of localized surface plasmon resonance peak(LSPR,from yellow to green)along with the scattering intensity ratio changes from individual Au@CeO_(2)NPs are *** activity can be quantified by calculating the ratio changes of individual Au@CeO_(2)*** assay reveals limit of detection(LOD)of 0.044 mU/mL and the linear range of 0.05–5.0 mU/mL,which are much lower than most of spectroscopic measurements in bulk ***,the recovery measurements in real samples are satisfactory and the capacity for practical application is *** a consequence,Au@CeO_(2)NPs used in this assay will find new applications for the ultrasensitive detection of enzyme activity.

关键词： Single particle imaging Dark field Gold nanoparticle Enzyme activity Colorimetric detection

The Effect of Branching Structure on the Properties of Entangled or Non-covalently Crosslinked Polyisoprene

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Chinese Journal of Polymer Science 2021年第1期39卷 113-121,I0008页

作者： Mo-Kun Chen Rong Zhang Mao-zhu tang Guang-Su Huang Yun-Xiang Xu College of Polymer Science&Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

The branching structures in natural rubber(NR) were believed to be critical for its superior mechanical properties. However, it is challenging to unravel the branching structure-function relationship of NR due to the complexity of the system. Herein, polyisoprene-(polyisoprene-g-polylactide)(PI-PLA) as model compound containing branching structure was designed and synthesized, which can improve the modulus, strength and viscoelasticity activation energy compared to those of the pristine polyisoprene(PI). The reason is that the branching structure contributes to the entanglement between polyisoprene chains. In order to probe the effect of branching structure on noncovalently crosslinked system, the polyisoprene block of PI-PLA was epoxidized and mixed with Fe3+ ions to introduce coordination bonds. Compared with the linear counterpart, the branching structure obviously enhanced activation energy of coordinated polyisoprenes, remarkably improving the mechanical properies of elastomer.

关键词： Natural rubber Branching structure Noncovalent interaction Polyisoprene

Experimental evaluation of the effect of an internal heat exchanger on a transcritical CO_2 ejector system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第2期12卷 146-153页

作者： Xiao-xiao XU Guang-ming CHEN Li-ming tang Zhi-jiang zhu Shuang LIU Institute of Refrigeration and Cryogenics State Key Laboratory of Clean Energy Utilization Zhejiang University Hangzhou 310027 China

This study presents experimental results focused on a performance comparison of a transcritical CO2 ejector system without an internal heat exchanger(IHX) (EJE-S) to a transcritical CO2 ejector system with an IHX(EJE-IHX-S) . The comparison includes the effects of changes in operating conditions such as cooling water flow rate and inlet temperature. Experiments are conducted to assess the influence of the IHX on the heating coefficient of performance(COPr) ,heating capacity,entrainment ratio,pressure lift,and other parameters. The primary flow rate of the EJE-IHX-S is higher than that of the EJE-S. The pressure lift and actual ejector work recovery are reduced when the IHX is added to the transcritical CO2 ejector system. Using a more practical performance calculation,the compression ratio in the EJE-S is reduced by 10.0%-12.1%,while that of EJE-IHX-S is reduced only by 5.6%-6.7% compared to that of a conventional transcritical CO2 system. Experimental results are used to validate the findings that the IHX weakens the contribution of the ejector to the system performance.

关键词： CO2 ejector system Transcritical cycle Heating coefficient of performance (COPr)

A Self-Healing Elastomer with Extremely High Toughness Achieved by Acylsemicarbazide Hydrogen Bonding and Cu^(2+)-Neocuproine Coordination Interactions

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Chinese Journal of Polymer Science 2024年第10期42卷 1425-1434,I0007页

作者： Xiao-Ming An Yi-Ping Wang tang-Song zhu Chong Xing Xu-Dong Jia Qiu-Hong Zhang Key Laboratory of High Performance Polymer Material and Technology of MOE Department of Polymer Science and EngineeringSchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210093China State Key Laboratory of Coordination Chemistry Nanjing UniversityNanjing210093China

Elastomers with high mechanical toughness can guarantee their durability during service ***-healing ability,as well as recyclability,can also extend the life of materials and save the consuming cost of the *** efforts have been dedicated to promoting the mechanical toughness as well as the self-healing capability of elastomers at the same time,while it remains a challenge to balance the trade-off between the above properties in one *** we proposed a molecular design driven by dual interactions of acylsemicarbazide hydrogen bonding and Cu^(2+)-neocuproine coordination *** introducing the reversible multiple hydrogen bonds and strong coordination bonds,we successfully fabricated an extremely tough and self-healing *** elastomer can achieve an impressive top-notch toughness of 491 MJ/m^(3).Furthermore,it boasted rapid elastic restorability within 10 min and outstanding crack tolerance with high fracture energy(152.6kJ/m^(2)).Benefiting from the combination of dynamic interactions,the material was able to self-repair under 80℃conveniently and could be reprocessed to restore the exceptional mechanical properties.

关键词： Metal-ligand coordination Hydrogen bond Ultra-tough elastomer Self-healing

The Relationship between Pendant Phosphate Groups and Mechanical Properties of Polyisoprene Rubber

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Chinese Journal of Polymer Science 2021年第4期39卷 465-473,I0006页

作者： Shi-Qi Li Mao-zhu tang Cheng Huang Rong Zhang Guang-Su Huang Yun-Xiang Xu College of Polymer Science&Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

It is still a great challenge to mimic the structure and function of natural rubber by introducing polar components into synthetic *** order to explore the function of phosphate groups on the mechanical properties of polyisoprene rubber,a terminally functionalized compound(PIP-P)containing phosphate groups was synthesized and further vulcanized to prepare the model compound *** analyzing the test results,it was found that these phosphate groups formed polar aggregates in non-polar polyisoprene rubber matrix,serving as an additional dynamic cross-linking sites,which increases the cross-linking density and improves mechanical *** influence of the phosphate groups on the strain-induced crystallization(SIC)was further investigated via synchrotron wide-angle X-ray diffraction(WAXD)*** phosphate group aggregates not only reduced the onset strain of SIC,but also slowed down the molecular chain mobility,which hinder the crystal lateral *** above results help us to gain a deeper understanding for the function of phosphate groups in the formation of"naturally occurring network"and guide the molecular design of next generation polyisoprene rubber.

关键词： Phosphate groups Strain-induced crystallization Naturally occurring network Natural rubber

Structural Evolution of PGA Nascent Fiber during Single Low-Temperature and Segmented High-Temperature Hot Stretching

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Chinese Journal of Polymer Science 2023年第7期41卷 1078-1092页

作者： Yu-Shuang Miao Hua-Shuai Cui Jin Guo Jin-tang zhu Yi-Guo Li Zong-Bao Wang School of Materials Science and Chemical Engineering Key Laboratory of Impact and Safety EngineeringMinistry of EducationNingbo UniversityNingbo315211China State Key Laboratory of Biobased Fiber Manufacturing Technology China Textile AcademyBeijing100025China

Polyglycolide (PGA) fibers applied as surgical sutures strongly depend on their microstructure. The structural evolution of PGA nascent fibers during single low-temperature stretching and segmented high-temperature stretching was analyzed based on a combination of in situ WAXD/SAXS and DSC measurements. The results indicated that the hot stretching was conducive to the crystal perfection and the local fragmentation and recrystallization of the lamellar crystals may occur under stress induction. The single low-temperature stretching of PGA nascent fibers could be divided into three stages: the stretching of amorphous regions, stretch-induced crystallization and the stretching of crystalline regions. The elongation at break of the fibers can be substantially increased by adopting a segmented stretching method, and the high-temperature stretching can also significantly increase the crystallinity and orientation. The amorphous orientation peak appearing in the low-temperature stretching was gradually converted to crystallization peak during the heating process, which greatly improved the crystallinity and orientation of the fibers. High-temperature stretching compared with low-temperature stretching was more favorable for crystal perfection and structural evolution, where lamellar crystals underwent stress-induced fragmentation recrystallization to transform to fibrous crystals as the strain increased.

关键词： PGA fiber Structural evolution Hot stretching

Vulcanization Kinetics of Graphene/Styrene Butadiene Rubber Nanocomposites

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Chinese Journal of Polymer Science 2014年第5期32卷 658-666页

作者： Mao-zhu tang Wang Xing 吴锦荣黄光速 Hui Li Si-duo Wu State Key Laboratory of Polymer Material Engineering College of Polymer Science and Engineering Sichuan University

This paper presents the influence of graphene on the vulcanization kinetics of styrene butadiene rubber （SBR） with dicumyl peroxide. A curemeter and a differential scanning calorimeter were used to investigate the cure kinetics, from which the kinetic parameters and apparent activation energy were obtained. It turns out that with increasing graphene loading, the induction period of the vulcanization process of SBR is remarkably reduced at low graphene loading and then levels off; on the other hand, the optimum cure time shows a monotonous decrease. As a result, the vulcanization rate is suppressed at first and then accelerated, and the corresponding activation energy increases slightly at first and then decreases. Upon adding graphene, the crosslinking density of the nanocomposites increases, because graphene takes part in the vulcanization process.

关键词： Graphene Styrene butadiene rubber Vulcanization kinetics.

Gate-Attention and Dual-End Enhancement Mechanism for Multi-Label Text Classification

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Computers, Materials & Continua 2023年第11期77卷 1779-1793页

作者： Jieren Cheng Xiaolong Chen Wenghang Xu Shuai Hua zhu tang Victor S.Sheng School of Computer Science and Technology Hainan UniversityHaikou570228China Hainan Blockchain Technology Engineering Research Center Hainan UniversityHaikou570228China School of Cyberspace Security Hainan UniversityHaikou570228China Department of Computer Science Texas Tech UniversityLubbock79409USA

In the realm of Multi-Label Text Classification(MLTC),the dual challenges of extracting rich semantic features from text and discerning inter-label relationships have spurred innovative *** studies in semantic feature extraction have turned to external knowledge to augment the model’s grasp of textual content,often overlooking intrinsic textual cues such as label statistical *** contrast,these endogenous insights naturally align with the classification *** our paper,to complement this focus on intrinsic knowledge,we introduce a novel Gate-Attention *** mechanism adeptly integrates statistical features from the text itself into the semantic fabric,enhancing the model’s capacity to understand and represent the ***,to address the intricate task of mining label correlations,we propose a Dual-end enhancement *** mechanism effectively mitigates the challenges of information loss and erroneous transmission inherent in traditional long short term memory *** conducted an extensive battery of experiments on the AAPD and RCV1-2 *** experiments serve the dual purpose of confirming the efficacy of both the Gate-Attention mechanism and the Dual-end enhancement *** final model unequivocally outperforms the baseline model,attesting to its *** findings emphatically underscore the imperativeness of taking into account not just external knowledge but also the inherent intricacies of textual data when crafting potent MLTC models.

关键词： Multi-label text classification feature extraction label distribution information sequence generation